I know this is an old thread but I have an A2 1.6 FSi with its engine management light on (sometimes flashing, sometimes solid) and it is generating a lot of different codes. Says it has multiple mis-fires yet it drives well, the airbag light has now come on, it says there are problems with the door locks (there aren't) - multiple codes, none of which make much sense.
I need an expert to help me work out what is happening. My only guess now is that an earth cable is corroded somewhere - any other ideas?